Common Core: High School - Algebra

This subject covers the foundational concepts and skills of algebra as outlined in the Common Core standards for high school students.

Basic Concepts

Functions and Their Representations

What Is a Function?

A function is a rule that assigns each input exactly one output. Think of it as a machine: you put something in, and you always get a specific result out.

  • Notation: \( f(x) \) means “the function of \( x \)”.

Ways to Show Functions

You can represent functions in different ways:

  • Equation: \( f(x) = 2x + 1 \)
  • Table: Showing input and output pairs.
  • Graph: Plotting points and drawing the line or curve.

Why Are Functions Useful?

Functions help us describe relationships, patterns, and changes in the world.

Real-World Connections

  • Predicting how much money you’ll have after saving a certain amount each week.
  • Figuring out how the temperature changes over time.

Key Features

  • Domain: All possible inputs.
  • Range: All possible outputs.

Examples

  • If \( f(x) = 3x \), then \( f(2) = 6 \)

  • Table: If \( x = 1, 2, 3 \), then \( f(x) = 4, 5, 6 \) if \( f(x) = x + 3 \)

In a Nutshell

Functions relate inputs to outputs, showing how things change together.

Key Terms

Function
A relationship where each input has exactly one output.
Domain
The set of all possible input values for a function.
Range
The set of all possible output values for a function.